As a very experienced hunter, there is no magic bullet or caliber that guarantees 1 shot stops. Great shot placement is where the solution is. Smart selection of purpose driven bullet design and construction is next for example. I own both 300BLK and 308. Ballistically they are very different. See my charts below. Note the average ft lbs at the muzzle for a 308 is around 2800 and the 300BLK 1400. Yes, you can split hairs with this grain of bullet or powder charge, but the 308 has a large and undeniable advantage over the 300BLK for terminal performance on game. That said, the 300BLK will certainly take hogs just fine at reasonably distances with smart choices for bullet design (my favorite is 110r TSX).

http://www.ballistics101.com/308_winchester.php

http://www.ballistics101.com/300aac_blackout.php